Folding step ladder



Aug. 11, 1959 I M. ROTH 2,899,009

FOLDING STEP LADDER Filed Aug. '25, 1958 3 Sheets-Sheet 1 INVENTOR. M lLT O N R OT H HTTURNEY W 11*," 1959 M. ROTH FOLDING STEP LADDER 5Sheets-Sheet 2 Filed Aug. 25, 1958 INVENTOR. MILTON ROTH HT'I'DRNEY' M.ROTH FOLDING STEP LADDER Aug. 11, 1959 3 Sheets-Sheet 3 Filed Aug. 25,1958 INVENTOR.

MILTON ROTH HTTURNEY dl States I 1 This invention relates generally toladders, and more particularly has reference to an extensiblestepladder.

Stepladders ordinally consume a large amount of space in the home, andit is, of course, desirable to avoid this as much as possible.Accordingly, one important :object of the present invention is toprovide -a collapsible, extensible stepladder so designed that when .itis collapsed and stored, it will occupy a very small amount of space ascompared to stepladders not having the telescopic or extensiblecharacteristics of the present invention.

Another object is to provide a collapsible stepladder of the characterstated which, when extended for use, will be characterized by itsstrength, resulting from the overlapping of difierent sections of thestepladder, to produce particularly effective side bracing meansonthestepladder.

Another object .is to provide a collapsible stepladder of the characterstated which will be capable of manufac- .ture as a comparatively lowcost, considering the decided benefits to be obtained from the usethereof.

A furtherobject is to provide an improved latch means operableautomatically responsive to extension of the stepladder, to releasablyhold thesections of the .ladder in their extended positions.

A further object is to provide said latch means on both the front andrear portions of the ladder, so that each of said portions will have aself-contained latch assembly operable when said portions move into anextended position.

A further object is to facilitate the retraction of the latches when thestepladder is to be collapsed, by reason of a novel arrangement whereinswinging of the front and rear portions of the ladder into contactingrelation will cause the latch means of said front and rear portions tobe connected for conjoint retraction. In this way, responsive merely toswinging of ladder portions toward each other, one is enabled to operatethe latches of both portions for the purpose of efiecting telescoping of.said portions to a fully retracted or collapsed condition.

A further object is to provide a collapsible stepladder as describedwhich in at least one form of the invention will be designed tofacilitate operation of the front and rear portions, so that each ofthem can be usable as an extension ladder. In this way, it is proposedto permit the collapsible stepladder to be readily separated into itsbasic component parts, to permit simultaneous use thereafter of twoextension ladders.

For further comprehension of the invention, and of the objects andadvantages thereof, reference will be had to the following descriptionand accompanying drawings, and to the appended claims in which thevarious novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

Fig. l is a front elevational View of the stepladder according to thepresent invention, in a fully collapsed condition.

atent 2,899,009 Patented Aug. 11, 1959 ice Fig. 2 is a side elevationalview of the ladder, fully collapsed.

Fig. 3 is a top plan view of the collapsed ladder as seen fromline 33 ofFig. 2.

Fig. 4 isa side, elevational view of the ladder in its extended or useposition.

Fig. 5 is a rear elevational view of the extended ladder, as seen fromtheright of Fig.4.

Fig. 6 is a vertical sectional view through the ladder in its extendedposition, taken substantially online 6-6 of Fig. 5.

Fig. 7 is a'greatly 'enlarged, transverse sectional view through therear portion of the ladder, taken on line 7--7 of Fig. 6-and showing thelatch means of said rear .portion.

Fig. 8 is a sectional view similar to and on the same scale as Fig. 7,takensubstantially on line 88 of Fig. 6, showingoneof thelath means ofthe front portion.

Fig. 9 is a perspective view, on approximately the same scale as Figs. 7and 8, of one of the latch blocks shown in Fig. 8.

Fig. '10 is a fragmentary, exploded, perspective view of the upperportion of a'rnodified form of the invention.

Referring to thedrawings indetail, the stepladder comprising the presentinvention includes a collapsible front .portion 1'0 and a-c-ollapsiblerear portion generally designated 12 and 'hingedly connected at itsupper end to the upper end of the front portion. The front portion com--prises three'telescopicsections in the illustrated example. However,the number of sections could be increased or decreased as desired.Sa'idsections comprise, in the illustrated embodiment, an upper section14, an intermediate section 16, and a bottom section 18.

Each of the sections 14, 16 and 18 will be described in turn. Thus,considering the construction of the upper section 14, this includes ahorizontally disposed, trans versely extending upper tread or step 20,comprising the topmost step of the ladder. Step '20, as may be notedfrom Fig. 6, can be formed of a length of channel metal material,opening downwardly. Obviously, the surface of this and of the remainingsteps could be roughened, corrugated, or otherwise formed not only toincrease the strengthof the step, but also to provide a non-slip surfacethereon.

In any event, step 20 at its opposite extremities is welded or otherwisefixedly secured to a pair of downwardly ex tending side rails of the topsection 14, designated at 22 and having their lengths inclined slightlyout of perpendicularity to the plane of the step 20 (see Fig. 6).

The respective side rails 22 are formed as outwardly facing channelseach having inturned guide flanges 24 extending along its respectivelongitudinal edges (see Fig. 4). To reinforce the side rails along theirmidwidth areas, there are provided longitudinally extending reinforcingribs 26 formed out of the material of the side rails. These cooperatewith the flanges 24 in rigidifying the respective side rails;

Intermediate its ends but closer to its lower than to its upper end,each side rail has a rectangular, latch-receiving opening 28 (Fig. 4)disposed medially between the opposite sides of the side rail.

Considering now the construction of the intermediate section, this, likethe top section, can be appropriately described as being generally of aninverted U-sha'pe. Thus, the intermediate section 16 includes ahorizontally, transversely extending intermediate step or tread 30, alsoformed as a downwardly opening channel, the back flange 31 of thechannel (Fig.- 6) being bent inwardly to provide clearance for pins ofthe latch means of the front portion, in a manner to be described infull detail hereafter.

The intermediate section includes intermediate side rails 32, thelengths of which are inclined correspondingly to the upper side rails22. Side rails 32 telescopically receive the lower portions of the siderails 22, and to this end, have inwardly turned or rolled longitudinalguide flanges 34 embracing the flanges 24. A longitudinal reinforcingrib 35 of each intermediate side rail 32 is slidably engaged with thecorresponding 26 of the adjacent, upper side rail 22. Intermediate theends of the respective side rails 32, but closer to the lower than tothe upper ends thereof, there are square, latch-receiving openings 36.

The bottom section 18 is also of the general shape of an inverted U, andhas a bottom tread 38 similar to the tread 30 (Fig. 6). This is weldedor otherwise fixedly secured at its opposite ends to depending lowerside rails 40. These have their lengths inclined correspondingly to thelengths of the intermediate and upper side rails. Lower side rails 40have longitudinal, inwardly turned guide flanges 42 embracing flanges-34(see Figs. 4 and 8). To transversely brace the lower section, there isprovided a crossbar 44 which can be formed of tubular metal stock asshown in Fig. 6, welded at its ends to the intermediate portions of therespective rails 40.

As will be seen from the above, the front portion 14 of the stepladdercomprises a plurality of telescopi cally related sections each of whichis of approximately inverted U-shape, the side rails or legs of eachsection telescoping in the side rails of the next lower section. Whenthe sections are fully collapsed, the horizontally disposed treads orbight portions thereof are all in closely spaced, superposed relation asshown in Fig. 1.

When extended as in Fig. 4, the front portion has its side railsoverlapped for substantial portions of their lengths as will be readilynoted from Fig. 4. This provides effective bracing along the oppositesides of the front portion 10, which bracing imparts greater strength tothe front portion than would normally be possessed thereby if it merelyhad, from its upper to its lower ends, one-piece, rigid side rails.

Turning now to the construction of the rear portion 12, the basicstructural arrangement of the component sections thereof is similar tothat of the front portion. Thus, the rear portion 12 includes upper,intermediate, and bottom sections generally designated 48, 50, and 52,respectively. Each of these, further, is of approximately invertedU-shape.

Considering the construction of the top section 48 of rear portion 12,this includes a transversely extending, upwardly arched handle 54 formedof tubular metal stock and projecting above the top step 20. Handle 54at its opposite ends is welded or otherwise fixedly secured to the upperends of top side rails 56 of rear portion 12, having (Fig. 4) inwardlyturned upper guide flanges 58 extending along opposite sides of areinforcing rib 59.

Intermediate section 50 includes a horizontally disposed crossbar 60formed from a length of channel material faced in a downward direction.This is rigid at its oppos1te ends with depending intermediate siderails 62, havmg lnwardly turned longitudinal flanges 64, embracingslidably the flanges 58. Lower section 52 includes a crossbar 66 similarto crossbar 60 though slightly wider than crossbar 60. This is rigid atitsopposite ends with side rails 68 having inwardly turned guide flanges70 embracing flanges 64 as best shown in Figs. 4 and 7.

Bracing the lowermost section (Fig. 5) is a crossbar 72 of tubular metalstock, welded at itsopposite endsto the intermediate portions of thelower side rails 68.

It will be seen that both the front and rear portions 10, 12 collapsesimilarly, being operable between fully collapsed positions shown inFig. 2 and fully extended positrons shown in Fig. 4.

. The portions 10, 12 are hingedly connected at their upper ends,through the provision of confronting, rightangular hinge brackets 74fixedly secured to and extend: mg rearwardly from the opposite ends ofthe top tread 20. The rearwardly projecting portions of the brackets 74are in embracing relation to the uppermost section 48 of the rearportion 12, and are pivotally connected to said rear portion by hingepins or rivets 76. The rear portion thus swings between its Fig. 2,non-use position in which it is in longitudinally contacting relation tothe front portion 10, and its operative position in which it is indownwardly divergent relation to the front portion 10 as shown in Fig.4.

Formed in' the several side rails 56, 62 and 68 are rectangularlatch-receiving openings 78, 80, 82, respectively.

Referring now to Figs. 7, 8 and 9, the invention includes identicallatch assemblies 84 mounted upon the undersides of the steps 30, 38, andidentical latch assemblies 86 mounted upon the undersides of thecrossbars 60, 66.

Considering first the construction of the latch assemblies 84 of thefront portion 10, since these are identical, the description of one willsufiice for both.

Each latch assembly 84 includes an elongated latch housing 88 ofrectangular cross section, extending horizontally between the oppositesides of the ladder section on which it is mounted. Thus, the upperlatch assembly 84 has its housing 88 welded at its opposite ends to theinner surfaces of the side rails 32. The lower latch assembly 84 has itshousing 88 welded to the inner surfaces of the lower side rails 40 asshown in Fig. 8.

In any event, each housing 88, at its opposite ends, communicates withthe latch-receiving openings of the particular section on which saidhousing is mounted, so that the assembly shown in Fig. 8 communicateswith openings 46 formed in side rails 40. Openings 46, in the preferredillustrated embodiment, are slightly smaller in area than thecross-sectional area of the housing 88.

Slidably mounted in the opposite ends of the housing 88 are elongated,solidly formed plungers or latch blocks 90, of a cross sectioncorresponding to the internal cross section of the housing 88. Blocks 90at their outer ends have beveled projections 92 comprising latchelements engageable in registered latch-receiving openings of theextended sections. Thus, in Fig. 8 latch elements 92 are engaged inregistered openings 46, 36 of the intermediate and lower sections 16,18, respectively.

Formed in the rear surfaces, of the latch blocks 90 are threadedrecesses 93, in which are engaged the threaded inner ends of elongated,straight, sharply pointed prongs or pins 94 projecting rearwardly towardthe rear portion 12 of the ladder.

A compression coil spring 96 is interposed between the latch blocks 90,exerting a continuous yielding pressure on the same tending to bias thesame outwardly from one another, to engage the latch elements in theregistered latch-receiving openings. In the rear wall of the housing 88there are longitudinal slots 98 through which the pins project, the pinssliding in the slots during the. movement of the latch blocks 90 towardand away from each other.

The latch assemblies 86 are almost identical to the assemblies 84, theonly difference being in the provision of flared sockets instead of pins94. Thus, latch assemblies have male elements engageable in femaleelements of the latch assemblies 86.

Each latch assembly 86 thus includes an elongated housing 100 extendingbetween and welded to the side rails of the associated section carryingthe assembly. Sliding in each housing 100 are plungers or latch blocks102 having at their outer ends beveled noses or projections 104, saidblocks being biased from one another by 'a compression, coil spring 106interposed therebetween. Each crossbar 60 and 66 has its front wall 87partially cut away to permit the forwardly projecting flared sockets orfemale elements 108 to extend in positions adapted to receive the pigs94. The front walls of the housing 100 have guide slots in which thesockets 108 are slidable.

Referring now to-Figs. 1-4, 'it'i s of cours'edesirable to provide bracemeans at opposite sides of ladder, connecting theextehded'front"andjrearportions-to limit the same against swinging outwardly from one anotherbeyond their use positions shownfin 'Fig. 4, Said brace means fu'rth'erlimits" the portions agaiiists'winging toward each otherfrom theirusepositions." 1

The brace means comprises elongated brace bars 103 at opposite sides ofthe ladder, pivoted at one end on pins 105' carried by the upperendportions of the side rails 40 of lower section 18, parts being shownbroken away. At this end, brace bars 103' have longitudinal sl'ots 107receiving the pins, said s1ots*(see Fig. 2) having lateral lockingextensions 1 09- atone end, parts being shown broken away.

Thus, the brace bars 103" are s'lidably, pivotally connected to thelower section 1 8 at opposite sides thereof. When' the ladder is stored;the bracebars extend longitudinally of the lower section 18 as shown inFig. 2' so as to occupy practically no extraspace,

When in use, the ladder appears as in Fig. 4 and the brace bars 103 areswung'to their Fig. 4.positions, having hooks 111 engageable overheaded" pins 113 that projectlaterally outwardly from-the-opposite sidesof the lower section 52 of rear-portion 1'2.

Obviously, other brace means may be employed, though that shown isbelieved to have particular advantages in respect to occupying no spacewhen the ladder is stored while still discharging its intended functionwhen the ladder is in use.

Referring now to Fig. 10, there is here shown a modified arrangementwith respect to the hinge connection to the front and rear portions. Inthis form of the invention, the ladder has a front portion 10 and a rearportion 12 with front portion 10 having an upper section 14. Rearportion 12 has an upper section 56 A top step is rigid with side rails22", while a handle 54 is rigid with side rails 56*. Thus, the laddershown in Fig. 10 is identical in all respects to that shown in Figs. 1-9with the exception of the hinge connection. In this form of theinvention there is a transversely elongated clevis member 110, in theform of an elongated bar having rearwardly projecting extensions 112. Acrossbar 114 of section 48 has forwardly projecting extensions 116embraced by extensions 112. The overlapped extensions of the clevismembers 110, 114 have openings adapted to receive an elongated hinge pin118 extending the full width of the ladder. This has a head at one end,the other end being threaded to receive a nut 120.

The clevis members are rigid with their respective sections. It will beapparent that by removal of the nut I120, pin 118 can be taken out,separating the front and rear portions 10, 12. Each thus becomes usableas an extension ladder, independently of the other.

In both forms of the invention, and considering the normal use of thedevice as a stepladder, one normally stores the ladder in the Fig. 2position. At this time, the ladder takes up very little space. At thistime, further, pins 94 are engaged in sockets 108. It is also importantto note that the latch-receiving openings of the several sections of thefront portion are out of full registration with each other. The same istrue of the corresponding opening of the sections of the rear portion 12or 12 Therefore, the several latching plungers are held in theirretracted position, when the device is collapsed as in Fig. 2.

When the device is to be used, one merely lifts the same by means of ahandle 54, using the handle not only for lifting and carrying thedevice, but also, for facilitating swinging of the front and rearportions away from each other from their Fig. 2, longitudinallycontacting positions. In any event, when the ladder is lifted, thelowermost sections automatically drop downwardly, as do the intermediatesections, so that all the sections move to their operative Fig. 6positions. When they' move tothese positions, with rear portion 12 swungrearwardly to disengage pins 94 from sockets 108 (Fig. 6-), the openingsof overlapped sections move into registration. Therefore, the latchplungers move outwardly to their Figs. 7 and 8 positions, locking theseveral sections intheir extended positionsautomat-ically.

Brace bars 103 are now-swungto their bracing positions, and the ladderis ready for use.

If the ladder is to be collapsed, one'merely disengages the brace bars103. 'Then, the front and rear portions are swung toward each other.When they move into longitudinally contacting relation, pins 94 enterthe sockets 1 08, so that corresponding latch assemblies 84, 86 arelinked for conjoint movement. Therefore, one merely grips the sockets108 of a latch-assembly 86, and moves them toward each other to retractthe plungers 102 to which said sockets or fem-ale projections aresecured. This causes the latch blocks 90 of the adjacent latch assembly84 to also be moved inwardly, due to the engagement of pins -94 in saidsockets or tubular projections 108. As soon as the four latch blocks ofthe interengaged sections are moved'inward'ly out of the latch-receivingopenings of the extended, associated ladder sections, saidassociated'sections telescope. After 'thisis done=with the lower setof-latchassemblies, the operation is carried out with respect to theassemblies 84, 86-underlying step 30 and crossbar 60, respectively. Thistelescopes the upper section into the intermediate section. The ladderis now fully collapsed, as in Fig. 2, ready for storage.

While I have illustrated and described the preferred embodiments of myinvention, it is to be understood that I do not limit myself to theprecise constructions herein disclosed and that various changes andmodifications may be made Within the scope of the invention as definedin the appended claims.

Having thus described my invention, what I claim as new, and desire tosecure by United States Letters Patent 1s:

1. A stepladder comprising upstanding front and rear ladder portionshingedly connected at their upper ends to swing relative to each otherbetween inoperative positions in substantial longitudinal contact witheach other and use positions in which they diverge in a downwarddirection, each portion comprising a plurality of sectionstelescopically related for retraction and extension between inoperativeand operative positions respectively, and means for releasably latchingthe several sections in said operative positions, each of the severalsections of said front and rear portions being approximately of invertedU-shape, each section of the front portion including a horizontal,transversely extending tread and side rails rigid with and dependingfrom the ends of the tread to cooperate with the tread in defining saidinverted U-shape, each section of the rear portion including ahorizontal, transverse cross member and side rails rigid with anddepending from opposite ends of said cross member to cooperate therewithin defining the inverted U-shape of each section of the rear portion,the side rails of several sections having inwardly turned guide flanges,the guide flanges of the side rails of each section embracing theflanges of the side rails of the section next above the same, theseveral side rails having openings registering in the extended positionsof the section to receive the latching means, said openings being out ofregister in the retracted positions of the several sections, saidlatching means comprising a plurality of latch assemblies on each of thefront and rear portions, each assembly including a pair of latchingplungers and spring means interposed between the latching plungers andbiasing the same outwardly from each other, into the registeredopenings, each plunger having lateral projections, the projections ofthe plungers of the latch assemblies of the front portion beinginterengageable with the corresponding projections of the latchassemblies of the rear portion, in the inopera- 7 tive, longitudinallycontacting positions of the front and rear portions.

j 2. A stepladder comprising upstanding front and rear ladder portionshingedly connected at their upper ends to swing relative to each otherbetween inoperative positions in substantial longitudinal Contact witheach other and use positions in which they diverge in a downwarddirection, each portion comprising a plurality of sectionstelescopically related for retraction and extension between inoperativeand operative positions respectively, and means for releasably latchingthe several sections in said operative positions, each of theseveralsections of said front and rear portions being approximately'of'inverted U-shape, each section of the front portion including ahorizontal, transversely extending tread and side rails rigid with anddepending from the ends of the tread to cooperate with the tread indefining said inverted U-shape, each section of the rear portionincluding a horizontal, transverse cross member and side rails rigidwith and depending from opposite ends of said cross member to cooperatetherewith in defining the invertedv U-shape of each section of the rearportion, the side rails of several sections having inwardly turned guideflanges, the guide flanges of the side rails of each section embracingthe flanges of the side rails of the section next above the same, theseveral side rails having openings registering in the extended positionsof the section to receive the latching means, said openings being out ofregister in the retracted positions of the several sections, saidlatching means comprising a plur ality of latch assemblies on each ofthe front and rear portions,;each, assembly including a pair oflatchingplunger sfand springmeans interposed between the latchingplungers andbiasing the same outwardly 'from each other, into the registeredopenings, each plunger having lateral projections, the projections ofthe plungers of the latch assemblies of the front portion beinginterengageable with the corresponding projections of the latchassemblies of the rear portion, in the inoperative, longitudinallycontacting positions of the front and rear portions, the projections ofone portion being of the male type and the projections of the otherportion being of the female type to receive said male projections,forconjoint operation of corresponding latch assemblies of the front andrearportions when said front and rear portions are inv longitudinallycontacting positions.

References Cited the file of this patent UNITED STATES PATENTS 1,712,942Smith May 14, 1929 2,194,856 Kostuk Mar. 26, 1940 2,588,959 CampbellMar. 11, 1952 2,827,216 Napolitano Mar. 18, 1958

